On 07:56:48 Mar 19, Norman Maurer wrote: > Hi all, > > im using freebsd 7.0 + gif interfaces + racoon + pf to filter stuff on > my box. After upgrading to freebsd 7.0 I see some strange behavior. I > see packets get dropped because of bad hdr length. The problems only > seems to happen on traffic between the local nets and nets routed via > ipsec. Here is a tcpdump snipped: > > block in on em5: 192.168.175.4.1107 > 192.168.116.6.22: tcp 544 [bad > hdr length 12 - too short, < 20] > > gif interface: > gif5: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> metric 0 mtu 1402 > tunnel inet 213.157.17.67 --> 213.23.198.131 > inet 192.168.116.1 --> 192.168.175.1 netmask 0xffffff00 > > > Any help is welcome.
A TCP header can never be less than 20 bytes. And 12 is odd since all headers are a multiple of 4 bytes (word boundary). Check your MTU of the PPPoE/PPPoA/Ethernet/WiFi or whatever datalink layer. I bet there is a problem there. Best, Girish -- "unix soi qui mal y pense" UNIX to him who evil thinks +------------------------------------------------------------------+ | GnuPG key : 0xC7BBF207 | http://wwwkeys.nl.pgp.net | | Fingerprint: 2AFF C264 20CE C80C DDFF CC15 AD3E F190 C7BB F207 | +------------------------------------------------------------------+
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